1. Field of the Invention
This invention relates to improvements in drop-bolt-type lock assemblies, and particularly to such an assembly operated from a protected high security lock cylinder.
2. Prior Art
It is known in the art that drop-bolt locks provide extremely good resistance to defeat by jimmying, chiseling, prying and the like.
However, even if a drop-bolt lock is highly resistant to defeat, it can be compromised if the cylinder which operates the lock bolt can be defeated.
It is also known in the art to protect lock cylinders by guard plates or the like. Nevertheless, there remains a need in the art to provide a drop-bolt lock and cylinder assembly which is highly resistant to defeat by jimmying, chiseling and prying.